Often, fruit is packed at the packing facility in quantity into packages, and the packages are labeled to indicate the type of fruit and its origin. However, increasingly, grocery stores are demanding that individual articles of fruit be labeled, to avoid check-out errors that might occur when articles of fruit that may look similar need to be distinguished, such as where the store carries two different varieties of apples, with one being higher priced. So it is becoming more common to label individual articles of fruit and other produce. Such labels typically carry the following information: (1) trade or certification mark; (2) produce variety identification; and (3) PLU (“price look-up”) or bar-code. Where a bar-code (or other scan-able code) is used, additional information is generally included, such as for tracing the article back to an original source.
There are hand-operated labeling devices that can be used at the point of sale by store personnel for this purpose, but it is usually more economical to provide such labels at the packing facility, at the time the produce is being sorted, inspected, gathered, and prepared for shipping.
Packing facilities typically have more than one “packing line,” and a single packing line can be required to apply labels to 150-300 million articles of produce annually. Thus, it is highly desirable to automate the process as much as possible.
Using fruit packing as an example, the packing line begins at the point where a bin containing articles of produce picked or otherwise harvested from the field is dumped for initial preparation. Where the articles are articles of fruit, they are washed, sorted, and waxed, all of these operations being performed semi-automatically. After initial preparation, the articles are ready to be placed onto a fully automated portion of the packing line referred to as a “sizer.” FIG. 1 shows the sizer 3 of the packing line 2, as well as a number of “tray filler sections” 4 that are fed in parallel by the sizer.
The sizer 3 has a number of parallel conveying “lanes” 5 for conveying the articles from a set of cameras 6 to the tray filler sections 4. Each conveying lane carries a series of cups 7, each cup being used to carry one article. The conveying lanes are computer controlled for speed, and the computer also tracks the location of each of the cups 7 as they are carried down the lanes.
After an article is introduced into a cup, the cup is caused to spin and in this spinning condition, the articles travel past the set of cameras 6. The cameras 6 image each article as it spins, and with this imaging information, the computer determines and associates with each article a definite average color.
After the articles are imaged, the spinning ceases and the cups proceed over a “weigh station” 8 for weighing the articles. The computer determines and associates with each article its measured weight, and the computer continues to track the location of the article as the cup carrying the article continues to travel down its respective lane.
The articles are next dropped out of their cups 7, as a result of the cups being tilted under computer control, onto conveyor belts 10 that function as the front ends of the tray filler sections 4. That is, there is a conveyor belt 10 for each tray filler section 4. At the tray filler sections, the articles are automatically loaded onto trays 11 that, typically, will function as packaging for the articles.
There are typically many more tray filler sections 4 than there are lanes 5, so the speed at which the articles are moving at the conveyor belts 10 may be reduced ten-fold, from about 150-200 feet per minute for each of the lanes to about 15-20 feet per minute at tray filler section.
With reference to FIG. 2, this speed reduction makes it practical for one or more human operators at a tray filler section to perform a visual inspection of the articles, referenced as 12, decide whether each article is acceptable or should be discarded, and arrange the articles in compartments 13 of the trays 11.
There are automated labeling systems known in the art for labeling the articles downstream of the weigh station 8 but upstream of the tray filling sections 4. Specifically, a labeling head 14 is provided for each of the lanes 5. Each labeling head has a dedicated reel 15 of labels, i.e., the labels are (spirally) flat-wound on a reel so as to form successive layers, one layer overlaying the next. Each layer is formed of two layers that together define a contiguous length of label material or “web:” (1) a layer of label material having printing on a top side and a bottom side that is coated with an adhesive, and (2) a removable “liner” material that does not adhere strongly to the adhesive and can be peeled therefrom.
Individual labels on the web are pre-defined on the liner by being pre-cut. Each label is applied to a corresponding article to be labeled after the label layer is peeled from the liner layer by running the web across a “peel plate.”
All of this activity must occur while articles are traveling at 150-200 feet per minute, which is a technical challenge. It is often the case that the labels are not completely applied and become dislodged during transit, and if there is any malfunction in a labeling head, an entire lane will be disabled.
The liner, after being peeled from the label, is taken up on another reel and must be discarded, imposing an additional cost. The mechanism is also typically exposed to and retains substantial amounts of adhesive and must be frequently cleaned to maintain satisfactory operation.
The present invention provides a more practical and cost effective automated labeling method and apparatus, particularly for labeling produce, and more particularly for labeling fruit.